ESP8266 nodeMCU

Other Hardware Displays
13

I tried everything, the LCD is on 3V, the LCD scanner returns the address 0x3F or another depending on the LCD I use, the pins are correct.

2
21000×1000 80.4 KB

The latest code I tried still does not work with this display 128x64:

//    FILE: I2C_LCD_minimal.ino
//  AUTHOR: Rob Tillaart
// PURPOSE: demo I2C_LCD library
//     URL: https://github.com/RobTillaart/I2C_LCD


#include "I2C_LCD.h"


I2C_LCD lcd(0x3F);


void setup()
{
  Serial.begin(9600);
  while (!Serial);
  Serial.println(__FILE__);
  Serial.print("I2C_LCD_LIB_VERSION: ");
  Serial.println(I2C_LCD_LIB_VERSION);
  Serial.println();

  Wire.begin();
  lcd.begin(20, 4);

  //  display fixed text once
  lcd.setCursor(0, 0);
  lcd.print("millis: ");
}


void loop()
{
  lcd.setCursor(8, 0);
  lcd.print(millis());
  delay(1000);
}


//  -- END OF FILE --

This is the latest diagnostic on a different library with the 128x64 display:

⸮dOI⸮⸮,MH⸮0⸮⸮l⸮⸮̤h|⸮⸮L⸮B⸮
********************************************************************
Serial Initialized
--------------------------------------------------------------------
I2CexpDiag - i2c LCD i/o expander backpack diagnostic tool
--------------------------------------------------------------------
hd44780 lib version: 1.3.2
--------------------------------------------------------------------
Reported Arduino Revision: 1.8.19
Arduino Board: ESP8266_NODEMCU_ESP12E
CPU ARCH: ESP8266 - F_CPU: 80000000
--------------------------------------------------------------------
SDA digital pin: 4 (GPIO4)
SCL digital pin: 5 (GPIO5)
--------------------------------------------------------------------
Checking for required external I2C pull-up on SDA - YES
Checking for required external I2C pull-up on SCL - YES
Checking for I2C pins shorted together - Not Shorted
--------------------------------------------------------------------
Scanning i2c bus for devices..
 i2c device found at address 0x3F
Total I2C devices found: 1
--------------------------------------------------------------------
Scanning i2c bus for all lcd displays (4 max)
LCD 0 begin() failed: -3
No working LCD devices

lcd-i2c-3
lcd-i2c-3769×629 45.4 KB

If I use this display(LCD 16x2), the diag becomes better, but still nothing is displayed:

⸮EP⸮V⸮⸮LH⸮⸮GxIh^XAT⸮⸮⸮Nh⸮0P
********************************************************************
Serial Initialized
--------------------------------------------------------------------
I2CexpDiag - i2c LCD i/o expander backpack diagnostic tool
--------------------------------------------------------------------
hd44780 lib version: 1.3.2
--------------------------------------------------------------------
Reported Arduino Revision: 1.8.19
Arduino Board: ESP8266_NODEMCU_ESP12E
CPU ARCH: ESP8266 - F_CPU: 80000000
--------------------------------------------------------------------
SDA digital pin: 4 (GPIO4)
SCL digital pin: 5 (GPIO5)
--------------------------------------------------------------------
Checking for required external I2C pull-up on SDA - YES
Checking for required external I2C pull-up on SCL - YES
Checking for I2C pins shorted together - Not Shorted
--------------------------------------------------------------------
Scanning i2c bus for devices..
 i2c device found at address 0x27
Total I2C devices found: 1
--------------------------------------------------------------------
Scanning i2c bus for all lcd displays (4 max)
 LCD at address: 0x27 | config: P01245673H | R/W control: Yes
Total LCD devices found: 1
--------------------------------------------------------------------
LCD Display Memory Test
Display: 0
 Walking 1s data test:	PASSED
 Address line test:	PASSED
--------------------------------------------------------------------
Each working display should have its backlight on
and be displaying its #, address, and config information
If all pixels are on, or no pixels are showing, but backlight is on, try adjusting contrast pot
If backlight is off, wait for next test

And the last display I have is.

1
1800×800 88.1 KB